Casual pants, such as dungarees and jeans, ordinarily have a waistband to which belt loops are sewn at intervals. In the manufacture of such trousers individual belt loops have been taken by a sewing machine operator, folded at opposite ends, and each end then sewn to the waistband. Such manual handling of individual belt loops has been a time consuming and costly process.
Recently, machines have been developed for automatically folding and positioning belt loops onto trouser waistbands preparatory to the belt loops being attached thereto by the use of a sewing machine. Examples of these machines are disclosed in U.S. Pat. Nos. 4,389,957, 4,393,800 and 4,287,842.
Though the just described machines have provided advancements in the art of automating trouser waistband manufacture, they have not eliminated the need for locating the positions along the waistband at which the various belt loops are to be attached. As described by U.S. Pat. No. 3,562,817, a system was developed in which waistbands were marked at the positions where the loops are to be attached, which marks were later sensed by sensors of the machinery used in placing the belt loops on the waistbands. However, this requires the separate steps of marking, detecting the marks and placing the loops on the waistband.
Waistbands are made in many different sizes for men's, women's, and children's trousers. The number of belt loops varies according to the size of the trousers and to the style of the trousers. In some cases the belt loops are equally spaced from one another along the length of the waistband while in other cases they are not. This wide variety in both the number and arrangement of the belt loops on the waistband presents a problem to the trouser manufacturer since such variety handicaps efficient manufacture.